EP1245801B1 - Abgasreiniger für eine Brennkraftmaschine - Google Patents

Abgasreiniger für eine Brennkraftmaschine Download PDF

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Publication number
EP1245801B1
EP1245801B1 EP02007169A EP02007169A EP1245801B1 EP 1245801 B1 EP1245801 B1 EP 1245801B1 EP 02007169 A EP02007169 A EP 02007169A EP 02007169 A EP02007169 A EP 02007169A EP 1245801 B1 EP1245801 B1 EP 1245801B1
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EP
European Patent Office
Prior art keywords
exhaust gas
catalyst device
particulates
temperature
particulate filter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP02007169A
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English (en)
French (fr)
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EP1245801A2 (de
EP1245801A3 (de
Inventor
Akira Mikami
Shinya Hirota
Kazuhiro Itoh
Takamitsu Asanuma
Koichi Kimura
Shunsuke Toshioka
Koichiro Nakatani
Toshiaki Tanaka
Masato Gotoh
Takekazu Ito
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Toyota Motor Corp
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Toyota Motor Corp
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Publication of EP1245801A3 publication Critical patent/EP1245801A3/de
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Publication of EP1245801B1 publication Critical patent/EP1245801B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2006—Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating
    • F01N3/2046—Periodically cooling catalytic reactors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00
    • F01N13/009—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series
    • F01N13/0097—Exhaust or silencing apparatus characterised by constructional features ; Exhaust or silencing apparatus, or parts thereof, having pertinent characteristics not provided for in, or of interest apart from, groups F01N1/00 - F01N5/00, F01N9/00, F01N11/00 having two or more separate purifying devices arranged in series the purifying devices are arranged in a single housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
    • F01N3/0233—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles periodically cleaning filter by blowing a gas through the filter in a direction opposite to exhaust flow, e.g. exposing filter to engine air intake
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/031—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters having means for by-passing filters, e.g. when clogged or during cold engine start
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/033—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices
    • F01N3/035—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices with catalytic reactors, e.g. catalysed diesel particulate filters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
    • F01N3/0821—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents combined with particulate filters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2006—Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/28—Construction of catalytic reactors
    • F01N3/2803—Construction of catalytic reactors characterised by structure, by material or by manufacturing of catalyst support
    • F01N3/2825—Ceramics
    • F01N3/2828—Ceramic multi-channel monoliths, e.g. honeycombs
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N9/00—Electrical control of exhaust gas treating apparatus
    • F01N9/002—Electrical control of exhaust gas treating apparatus of filter regeneration, e.g. detection of clogging
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2250/00—Combinations of different methods of purification
    • F01N2250/02—Combinations of different methods of purification filtering and catalytic conversion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2330/00—Structure of catalyst support or particle filter
    • F01N2330/06—Ceramic, e.g. monoliths
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2510/00—Surface coverings
    • F01N2510/06—Surface coverings for exhaust purification, e.g. catalytic reaction
    • F01N2510/065—Surface coverings for exhaust purification, e.g. catalytic reaction for reducing soot ignition temperature
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2570/00—Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
    • F01N2570/16—Oxygen
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Definitions

  • the invention relates to an exhaust gas purifier for internal combustion engine.
  • particulates mainly composed of soot are contained in the exhaust gas. Since such particulates are harmful substance, it is proposed that a particulate filter for collecting the particulates before being discharged to the atmosphere is disposed in an exhaust system of the engine. However, in order to prevent the increase of exhaust gas resistance due to the clogging, the collected particulates should be combusted. In such filtering regeneration, the particulates may be ignited for the combustion at about 600 °C, but the exhaust gas temperature of the diesel engine is generally lower than 600 °C and it is necessary for the filter itself to be heated.
  • the particulates on the filter are continuously combusted at the temperature of about 400 °C which is the normal temperature of the diesel engine exhaust gas by adding the platinum metal and alkaline-earth metals to the filter.
  • the temperature of the exhaust gas is always maintained at 400 °C and depending on the driving condition of the engine, a great amount of the particulates may be discharged from the diesel engine and accumulated gradually on the filter, which are not combusted at each timing.
  • the exhaust gas purifier for the internal combustion engine includes a particulate filter disposed in the engine exhaust system for collecting the particulates and reversing means that reverse an exhaust gas upstream side and an exhaust gas downstream side of the particulate filter.
  • the collected particulates by the filter are oxidized and the filter includes a collecting wall for collecting the particulates.
  • the collecting wall includes first and second collecting surfaces, which are alternately used for collecting the particulates by reversing the exhaust gas upstream side and downstream side of the filter by the reversing means.
  • a catalyst device is provided adjacent to the particulate filter at the position of always keeping downstream side of the filter.
  • Some particulates may be left on the first collecting surface of the particulate filter collecting wall due to insufficient oxidization according to the driving condition.
  • the reversing of the exhaust gas upstream side and downstream side by the reversing means will not let the particulates be accumulated on the first collecting surface of the collecting wall and a gradual oxidization removal of the particulates is possible.
  • the second collecting surface of the collecting wall the collection and oxidization of the particulates begin.
  • the amount of the collected particulates at each collecting surface can be reduced compared to the collection by using a single collecting surface. This will be advantageous in oxidization removal of the particulates to obviate the accumulation of the particulates on the filter to eventually prevent clogging of the filter.
  • the catalyst device since the catalyst device is provided always at the downstream of the particulate filter adjacent thereto, the catalyst device functions relatively effectively by the temperature increase through the heat conductivity from the particulate filter to reduce a possible large amount discharge of the harmful substances other than the particulates contained in the exhaust gas.
  • the collecting wall may carry an active oxygen release agent to oxidize the particulates by active oxygen released from the active oxygen release agent.
  • the active oxygen release agent captures and retains the surrounding excess oxygen and discharges the collected oxygen in the form of active oxygen when the surrounding oxygen concentration is decreased.
  • the catalyst device can be structured to carry the oxidization catalyst.
  • the catalyst device can be structured to carry the NOx catalyst.
  • the reversing means may include a valve body, and the exhaust gas upstream side and downstream side of the particulate filter may be reversed by changing the position of the valve body from a first position to a second position, and the exhaust gas may flow into the catalyst device without passing through the particulate filter when the valve body is positioned at an intermediate position between the first and second positions.
  • valve body can be positioned at the intermediate position immediately after the engine starts.
  • the exhaust gas purifier device may include a temperature detecting device that detects or assumes a temperature of the catalyst device, and when the temperature detected or assumed by this temperature detecting means is not within a predetermined temperature range, the valve body may be set to be the intermediate position for changing the exhaust gas condition to control the catalyst device temperature to be within the predetermined range.
  • the exhaust throttle valve may be provided in the engine exhaust gas system, and the position of the valve body may be controlled at the intermediate position immediately before the exhaust throttle valve is opened.
  • the valve body when the engine is under deceleration, the valve body may be positioned at the intermediate position, and at the same time the temperature of the exhaust gas may be increased or the deoxidization substances in the exhaust gas may be increased.
  • the reversing means may include a valve body, and may reverse the exhaust gas upstream side and the exhaust gas downstream side of the particulate filter by switching the valve body from a first position to a second position, and the catalyst device may be arranged adjacent to a downstream of the valve body.
  • the catalyst device may be arranged closer to the internal combustion engine than the particulate filter, and the catalyst device may be connected to the particulate filter so that the exhaust gas that flows out the particulate filter flows into the catalyst device.
  • the catalyst device may include a partition wall formed by porous material and divides the inside of the catalyst device into a plurality of axial spaces, and a flow amount control portion that is arranged at at least one of an upstream end and an downstream end of the axial space and controls a flow amount of the exhaust gas.
  • the flow amount control portion may be arranged at the upstream end or the downstream end of the partition wall which surrounds one of two adjacent axial spaces.
  • the flow amount control portion may be a plug which is arranged at one of the upstream side and the downstream side of each axial apace and prevents the exhaust gas from flowing.
  • the flow amount control portion may be a tapered portion which enlarges or reduces an opening area of the axial space.
  • the tapered portion may be provided with a passage which has a cross section area smaller than a cross section area of the axial space.
  • the tapered portion may be formed by deformation of the partition wall.
  • the flow amount control portion may be a catalyst coating layer that carries a catalyst on the partition wall.
  • both of the particulate filter and the catalyst device may be arranged in a housing.
  • the catalyst device may be positioned around the particulate filter.
  • Fig. 1 shows an exhaust gas purifier employed in a four-stroke type diesel engine according to the embodiment of the invention.
  • Fig. 2 is an enlarged sectional view of a combustion chamber of the diesel engine in Fig. 1.
  • Fig. 3 is a bottom view of the cylinder head of the diesel engine in Fig. 1.
  • Fig. 1 and Fig. 2 show an engine 1, a cylinder block 2, a cylinder head 3, a piston 4, a cavity 5a, a combustion chamber 5 in the cavity 5a, an electronic fuel injection valve 6, a pair of intake valves 7, an intake port 8, a pair of exhaust valves 9, and an exhaust port 10.
  • the intake port 8 is connected to a surge tank 12 through a corresponding intake branch 11.
  • the surge tank 12 is connected to an air cleaner 14 via an intake duct 13.
  • a throttle valve 16 driven by an electric motor 15 is disposed in the intake duct 13.
  • the exhaust port 10 is connected to an exhaust manifold 17.
  • the exhaust manifold 17 is provided with an air-fuel ratio sensor 21.
  • the exhaust manifold 17 and the surge tank 12 are connected to each other by an EGR passage 22 and the electrically controlled EGR control valve 23 is provided within the EGR passage 22.
  • each fuel injection valve 6 is connected to a fuel reservoir, namely, a so-called common rail 26 through a fuel supply pipe 25.
  • the common rail 26 is supplied with fuel from an electronic fuel pump 27 whose discharge amount is variable.
  • the fuel that has been supplied to the common rail 26 is supplied to the fuel injection valve 6 through each fuel supply pipe 25.
  • a fuel pressure sensor 28 for detecting the fuel pressure in the common rail 26 is fitted thereto. Based on the output signal from the fuel pressure sensor 28, the discharge amount of the fuel pump 27 is controlled such that the fuel pressure in the common rail 26 becomes equal to a target fuel pressure.
  • An electronic control unit 30 is inputted an output signal from the air-fuel ratio sensor 21 and an output signal from the fuel pressure sensor 28.
  • a load sensor 41 generating an output voltage proportional to the depression amount L of an accelerator pedal 40 is connected thereto.
  • An output voltage of the load sensor 41 is inputted to the control unit 30.
  • a crank angle sensor 42 which generates an output pulse every time a crankshaft rotates for example by 30°CA, is connected to the control unit 30.
  • the electric control unit 30 operates fuel injection valve 6, electric motor 15, the EGR control valve 23, and the fuel pump 27 based on each output signal.
  • the fuel injection valve 6 is formed by a holed nozzle with six nozzle openings and fuel F is injected from the nozzle openings in a lower direction relative to the horizontal direction with an equal interval.
  • two fuel sprays F among the six are injected along the underside of the valve body of each exhaust valve 9.
  • Figs. 2 and 3 show the fuel injection at the end of the compression stage. The fuel sprays F advance toward the internal surface of the cavity 5a and ignited for combustion.
  • Fig. 4 shows the additional fuel injection condition from the fuel injection valve 6 at the maximum lifting amount of the exhaust valve 9 during the exhaust stage.
  • the main fuel injection Qm is made at the compression top dead center as shown in Fig. 5 and then the additional fuel Qa is injected at the middle of the exhaust stage.
  • the fuel sprays F advancing toward the valve body of the exhaust valve 9 advance toward the position between the back of the umbrella portion of the injection valve 6 and the exhaust port 10.
  • the two nozzle openings among the six of the fuel injection valves 6 are formed to advance toward the position between the back of the umbrella portion of the injection valve 6 and the exhaust port 10, when the additional fuel Qa is injected during the exhaust valve 9 being opened.
  • the injected fuel sprays F collide on the back of the umbrella portion of the exhaust valve 9 and collided fuel sprays F reflect on the back of the umbrella portion of the valve 9 to advance toward the exhaust port 10.
  • Fig. 6 shows an output torque change when the air-fuel ratio A/F (horizontal axis in Fig. 6) is changed by changing throttle opening degree and the EGR ratio during the engine under low load operation and experimental examples of the exhaust amount change of smoke, HC, CO and NOx. As shown in the examples of Fig. 6, the EGR ratio becomes larger when the air-fuel ratio A/F becomes smaller and under the theoretical air-fuel ratio (about 14.6) the EGR ratio becomes 65% or more.
  • Fig. 7A shows the combustion pressure change in the combustion chamber 5 at the most increased smoke amount around the air-fuel ratio being 21 and Fig. 7B shows the combustion pressure change in the combustion chamber 5 at substantially zero level smoke amount around the air-fuel ratio being 18.
  • the combustion pressure at the smoke amount of zero shown in Fig. 7B is lower than the condition of large amount of smoke being generated as shown in Fig. 7A.
  • the HC at this stage may be a precursor of soot or the earlier stage HC discharged from the combustion chamber 5. More research has been conducted and we found the fact that when the temperature of fuel in the combustion chamber and the surrounding gas are lower than a certain temperature, the soot growth stops on the way and no soot is generated and when the temperature becomes a certain level, the soot is generated.
  • Such certain temperature to form soot or precursor of soot cannot be defined due to the various factors involved such as fuel type or air-fuel ratio and compression ratio, but it deeply relates to the generation of the NOx.
  • the certain temperature can be defined to a certain level from the generation amount of NOx.
  • the EGR ratio increases, the temperature of fuel or the surrounding gas decreases to reduce the NOx generation amount.
  • the NOx generation amount is about 10 p.p.m or less, the soot is not generated. Accordingly, the certain temperature is approximately equal to the temperature at NOx generation amount of 10 p.p.m or less.
  • the post-treatment using simply the catalyst having an oxidization function cannot purify the soot.
  • using such catalyst having an oxidization function can easily purify the precursor of soot or the earlier stage HC. It is therefore, effective to purify the exhaust gas by discharging hydrocarbon under the conditions of the precursor of soot or the earlier stage HC from the combustion chamber 5 as well as reducing the generation of the NOx amount.
  • the circumstances are slightly different if there is fuel in the mixed gas composed of a great amount of inactive gas and a small amount of air.
  • fuel vapors are diffused around, react with the oxygen mixed into inactive gas, and burn.
  • ambient inactive gas absorbs the combustion heat, the combustion temperature does not increase appreciably. Namely, it is possible to maintain the combustion temperature low.
  • the presence of inactive gas plays an important role in reducing the combustion temperature and the endothermic effect of inactive gas makes it possible to maintain the combustion temperature low.
  • the maintaining of the temperature of fuel and ambient gas lower than a temperature corresponding to the production of soot requires such an amount of inactive gas that can absorb heat sufficiently. Accordingly, the required amount of inactive gas increases in proportion to the increase in the amount of fuel. In this case, the endothermic effect is strengthened in proportion to the specific heat of inactive gas. Thus, it is desired that a gas having a great specific heat be used as inactive gas. In this respect, since CO 2 and EGR gas have a relatively great specific heat, it may conclude that EGR gas can be desirably used as inactive gas.
  • Fig. 9 shows the relation between the EGR ratio and the smoke concentration when EGR gas is used as inactive gas and the cooling degree of EGR gas is changed.
  • Fig. 9 shows curves A, B, and C.
  • the curve A indicates a case where the temperature of EGR gas is maintained approximately at 90°C by intensively cooling EGR gas.
  • the curve B indicates a case where EGR gas is cooled by a compact cooling unit.
  • the curve C indicates a case where EGR is not cooled forcibly. If EGR gas is cooled intensively as indicated by the curve A shown in Fig. 9, the generation amount of soot reaches its peak when the EGR ratio is slightly lower than 50%. In this case, almost no soot is generated if the EGR ratio is made approximately equal to or higher than 55%.
  • the EGR ratio where the generation amount of soot reaches its peak decreases slightly, and the lower limit of the EGR ratio where almost no soot is generated also decreases slightly.
  • the lower limit of the EGR ratio where almost no soot is generated changes depending on the cooling degree of EGR gas and the engine load.
  • Fig. 10 shows the amount of the mixed gas composed of EGR gas and air required for maintaining the temperature of fuel and ambient gas lower than a temperature corresponding to the production of soot, the ratio of air to the mixed gas, and the ratio of EGR gas to the mixed gas, in the case where EGR gas is used as inactive gas.
  • the axis of ordinate represents the total amount of the intake gas that can be introduced into the combustion chamber 5
  • a chained line Y represents the total amount of the intake gas that can be introduced into the combustion chamber 5 when the supercharging operation is not being performed.
  • the axis of abscissa represents the required load.
  • the ratio of air namely, the amount of air in mixed gas indicates the amount of air required for complete combustion of injected fuel. Namely, in the case shown in Fig. 10, the ratio of the amount of air to the amount of fuel injection is equal to the theoretical air-fuel ratio.
  • the ratio of EGR gas namely, the amount of EGR gas in mixed gas indicates the minimum amount of EGR gas required for maintaining the temperature of fuel and ambient gas lower than a temperature corresponding to the formation of soot, during combustion of injected fuel. This minimum required amount of EGR gas corresponds to the EGR ratio that is approximately equal to or higher than 55%. In the embodiment shown in Fig. 10, the EGR ratio is equal to or higher than 70%.
  • the amount of the heat absorbed by EGR gas must be increased in order to maintain the temperature of fuel and ambient gas lower than a temperature corresponding to the production of soot.
  • the amount of EGR gas must be increased in proportion to the increase in fuel injection amount.
  • the amount of EGR gas must be increased in proportion to the increase in required load.
  • the total amount of the intake gas X that is required to prevent the generation of soot exceeds the total amount of the intake gas Y which is the upper limit of the gas X introduced into the combustion chamber 5.
  • the total intake gas X corresponds to the total intake gas upper limit Y when the supercharging operation is not being performed.
  • the air amount has to be reduced slightly to increase the EGR gas amount thereby to burn the fuel under a relatively rich air-fuel ratio.
  • Fig. 10 shows a case that the fuel is combusted under the theoretical air- fuel ratio.
  • the soot generation is prevented and at the same time the NOx amount can be restricted to 10 p.p.m max. even the air amount is reduced from the amount shown in Fig. 10 (to enrich the air-fuel ratio).
  • the soot generation is prevented and at the same time the NOx amount can be restricted to 10 p.p.m maximum, even the air amount is increased from the amount shown in Fig. 10 (to lean the air-fuel ratio to the average value between 17 and 18).
  • the combustion temperature is maintained low, the excessive fuel does not grow into soot. Consequently, no soot is produced.
  • the generation amount of NOx is also considerably small.
  • a small amount of soot is produced in response to a increase in the combustion temperature when the average air-fuel ratio is lean or when the air-fuel ratio is theoretical.
  • the combustion temperature is maintained low, no soot is produced. Furthermore, the generation amount of NOx is also considerably small.
  • the temperature of fuel and ambient gas during combustion in the combustion chamber can be made equal to or lower than a temperature where the growth of hydrocarbons is stopped before its completion, only when a relatively small amount of heat is released due to combustion, namely, when the engine load is intermediate or low.
  • first combustion namely, low-temperature combustion is carried out with the temperature of fuel and ambient gas during combustion being maintained equal to or lower than a temperature where the growth of hydrocarbons is stopped before its completion.
  • second combustion namely, normal combustion is carried out.
  • the first combustion namely, low-temperature combustion refers to the combustion of a type wherein the amount of inactive gas in the combustion chamber is greater than the amount of inactive gas corresponding to a maximum generation amount of soot and wherein almost no soot is generated
  • the second combustion namely, normal combustion refers to the combustion of a type wherein the amount of inactive gas in the combustion chamber is smaller than the amount of inactive gas corresponding to a maximum generation amount of soot.
  • Fig. 11 shows a first operation zone I, where the first combustion, namely low-temperature combustion, is carried out and a second operation zone II, where the second combustion, namely, normal combustion is carried out.
  • the axis of ordinate L represents the depression amount of the accelerator pedal 40, namely, the required load
  • the axis of abscissa N represents the engine speed.
  • X(N) represents a first border between the first operation zone I and the second operation zone II
  • Y(N) represents a second border between the first operation zone I and the second operation zone II.
  • a shift of the operation zone from the first operation zone I to the second operation zone II is determined based on the first border X(N), and a shift of the operation zone from the second operation zone II to the first operation zone I is determined based on the second border (N). That is, if the required load L exceeds the first border X(N) expressed as a function of the engine speed N during low-temperature combustion with the engine being in the first operation zone I, it is determined that the operation zone has shifted to the second operation zone II, and normal combustion is carried out. If the required load L drops below the second border Y(N) expressed as a function of the engine speed N, it is determined that the operation zone has shifted to the first operation zone I, and low-temperature combustion is carried out again.
  • Fig. 12 shows the output of an air-fuel ratio sensor (not shown). As shown in Fig. 12, the output current I of the air-fuel ratio sensor changes depending on the air-fuel ratio A/F. Thus the air-fuel ratio can be detected from the output current I of the air-fuel ratio sensor.
  • Fig. 13 shows how the opening of the throttle valve 16, the opening of the EGR control valve 25, the EGR ratio, the air-fuel ratio, the fuel injection timing and the fuel injection amount change as the required load L changes.
  • the opening of the throttle valve 16 gradually increases approximately from its full-closed state to an opening of two-thirds as the required load L increases, and the opening of the EGR control valve 25 gradually increases approximately from its full-closed state to its full-open state as the required load L increases.
  • the EGR ratio is approximately equal to 70% and the air-fuel ratio is somewhat lean.
  • the opening degree of the throttle valve 16 and the EGR control valve 25 are controlled such that the EGR ratio becomes approximately equal to 70% and that the air-fuel ratio becomes somewhat lean.
  • fuel injection is carried out before the compression top dead center TDC.
  • the fuel injection start timing ⁇ S is retarded in proportion to the increase in the required load L.
  • the fuel injection end timing ⁇ E is also retarded in proportion to the retardation in the fuel injection start timing ⁇ S.
  • the throttle valve 16 is closed approximately to its full-closed state and the EGR control valve 25 is also closed approximately to its full-closed state.
  • the throttle valve 16 is closed approximately to its full-closed state, the pressure in the combustion chamber 5 at the beginning of compression decreases and thus the compression pressure decreases. If the compression pressure decreases, the compression work done by the piston 4 decreases and thus the vibration of the engine 1 is damped. That is, during idling operation, the throttle valve 16 is closed approximately to its full-closed state to damp the vibration of the engine 1.
  • the opening of the throttle valve 20 is increased stepwise from the opening of two-thirds toward its full-open state.
  • the EGR ratio is reduced stepwise approximately from 70% to 40% or less, and the air-fuel ratio is increased stepwise. That is, since the EGR ratio exceeds an EGR ratio zone (see Fig. 9) where a great amount of smoke is generated, a shift of the operation zone of the engine from the first operation zone I to the second operation zone II do not cause generation of a great amount of smoke.
  • the second operation zone II normal combustion is carried out.
  • the throttle valve 16 In the second operation zone II, the throttle valve 16 is mostly maintained in its full-open state and the opening of the EGR control valve 25 is gradually reduced in proportion to the increase in the required load L.
  • the EGR ratio decreases in proportion to the increase in the required load L
  • the air-fuel ratio decreases in proportion to the increase in the required load L.
  • the air-fuel ratio remains lean even if the required load L has increased.
  • the fuel injection start timing ⁇ S is close to the compression top dead center TDC.
  • Fig. 14 shows the air-fuel ratios A/F in the first operation zone I.
  • the air-fuel ratio is lean in the first operation zone I, and the air-fuel ratio A/F becomes leaner as the required load L decreases in the first operation zone I. That is, the heat release value resulting from combustion decreases in proportion to the decrease in the required load L.
  • the possibility of carrying out low-temperature combustion increases in proportion to the decrease in the required load L even if the EGR ratio has been reduced.
  • the air-fuel ratio increases if the EGR ratio is reduced.
  • the target air-fuel ratio A/F is increased in proportion to the decrease in the required load L.
  • the fuel consumption rate is enhanced in proportion to the increase in the target air-fuel ratio A/F.
  • the target air-fuel ratio A/F is increased in proportion to the decrease in the required load L.
  • the target openings ST of the throttle valve 16 required for making the air-fuel ratio equal to the target air-fuel ratios shown in Fig. 14 are stored in advance in the ROM 32 in the form of a map as a function of the required load L and the engine speed N as shown in Fig. 15A.
  • the target openings SE of the EGR control valve 23 required for making the air-fuel ratio equal to the target air-fuel ratios shown in Fig. 14 are stored in advance in the ROM 32 in the form of a map as a function of the required load L and the engine speed N as shown in Fig. 15B.
  • Fig. 16 shows the target air-fuel ratios A/F during the second combustion, namely, normal combustion.
  • the target openings ST of the throttle valve 16 required for making the air-fuel ratio equal to the target air-fuel ratios are stored in advance in the ROM 32 in the form of a map as a function of the required load L and the engine speed N as shown in Fig. 17A.
  • the target openings SE of the EGR control valve 23 required for making the air-fuel ratio equal to the target air-fuel ratios are stored in advance in the ROM 32 in the form of a map as a function of the required load L and the engine speed N as shown in Fig. 17B.
  • the first combustion in other words, the low temperature combustion and the second combustion, in other words, normal combustion are switched based on the depression amount L of accelerator 40 and engine rotational number N and at each combustion stage, the openings of throttle valve 16 and EGR valve are controlled by the map shown in Fig. 15 or 17.
  • Fig. 18 shows a plane view of the exhaust purifier and Fig. 19 is a side view of the purifier of Fig. 18.
  • the exhaust gas purifier includes a central conduit member 71 and a cover member 72 surrounding the central conduit member 71.
  • the upstream end of the central conduit member 71 is connected to the downstream side of the exhaust manifold 17 through the exhaust pipe 18 and the downstream end is connected to a downstream exhaust pipe 74 via a muffler for discharging the exhaust gas to the atmosphere.
  • the central conduit member 71 includes an upstream portion 71b provided with a valve body 71a, a central stream portion 71c positioned immediately down side of the upstream portion 71b and a downstream portion 71d positioned immediately down side of the central stream portion 71c.
  • a first opening 71e and a second opening 71f opposite thereto are formed on the side surface of the upstream portion 71b.
  • the valve body 71a is rotated to be in two interrupting positions for interrupting the upstream portion 71b between the upstream and downstream by rotation of a vacuum actuator or a step motor.
  • the upstream side and the first opening 71e are in communication and at the same time the downstream side and the second opening 71f are in communication.
  • the upstream side and the second opening 71f are in communication and at the same time the downstream side and the first opening 71e are in communication.
  • a temperature sensor 76 is provided in the central stream portion 71c in which the catalyst device 73 is disposed, at the direct downstream of the catalyst device 73 for detecting the exhaust gas temperature therein.
  • a particulate filter 70 with an elongated circular shape in cross section is disposed together with an outside case 70a and penetrates through the downstream portion 71d along the side surface.
  • the exhaust gas flows from the upstream side of the upstream portion 71b through the first opening 71e to a space between the cover member 72 and the central conduit member 71 as shown in arrows in Figs. 19 and 20.
  • the exhaust gas then passes through the particulate filter 70 through the second opening 71f and flows into the upstream portion 71b again. Thereafter, the exhaust gas flows around the outside case 70a of the filter 70 and flows toward the downstream exhaust pipe 74.
  • the exhaust gas flows from the upstream side of the upstream portion 71b through the second opening 71f to the space between the cover member 72 and the central conduit member 71 as shown in arrows in Fig. 20.
  • the exhaust gas then passes through the particulate filter 70 in opposite direction to the case of the one interrupting position and flows through the first opening 71e and flows into the upstream portion 71b again. Thereafter, the exhaust gas flows around the outside case 70a of the filter 70 and flows toward the downstream exhaust pipe 74.
  • valve body 71a can be also positioned at an intermediate position between the two interrupting positions. At this intermediate position, the upstream portion 71b of the central conduit member 71 is open, the exhaust gas flows directly into the catalyst device 73 disposed in the central stream portion 71c without passing through the space between the cover member 72 and the central conduit member 71, in other words, without passing through the particulate filter 70.
  • the exhaust gas purifier according to the invention can be simply constructed and by switching the interrupting position from one place to the other to reverse the exhaust gas flow path between the downstream and upstream sides. Further, when the valve body 71a is positioned at the intermediate between the two interrupting positions, the exhaust gas can bypass the particulate filter 70.
  • the particulate filter is usually required to have a large opening area for easy passing of the exhaust gas, but according to this embodiment, a large opening area can be provided without influencing on the vehicle installability as shown in Fig. 18.
  • An exhaust throttle valve 75 is provided in the exhaust pipe 18 as shown in Fig. 18.
  • Figs. 22A and 22B show the filter 70 structure and Fig. 22A is a front view of the particulate filter and Fig. 22B is the side view thereof.
  • the particulate filter 70 is of an elongated circular shape and has a honeycomb structure made from a porous material such as cordierite.
  • the filter is a wall-flow type and has a plurality of spaces in axial direction and finely divided by the partition walls extending in axial direction. One of the adjacent two spaces in axial direction is closed at the downstream side of the exhaust gas by a plug 52, and the other is closed at the upstream side of the exhaust gas by the plug 53.
  • alumina is used as oxidization removal of the particulates on both side surfaces of the partition wall 54 and preferably on the front surface of the fine holes in the partition wall 54 and the following active oxygen release agent and noble metal catalyst are carried thereby.
  • platinum Pt is used and as an active oxygen release agent at least one material selected from alkaline metals such as kalium K, natrium Na, lithium Li rubidium Rb and cesium Cs, alkaline earth elements such as barium Ba strontium Sr and calcium Ca, and rare earth elements such as lanthanum La and yttrium Y is used.
  • alkaline metals such as kalium K, natrium Na, lithium Li rubidium Rb and cesium Cs
  • alkaline earth elements such as barium Ba strontium Sr and calcium Ca
  • rare earth elements such as lanthanum La and yttrium Y is used.
  • an alkaline metal or an alkaline earth metal that is higher in ionization tendency than calcium Ca namely, kalium K, lithium Li, cesium Cs, rubidium Rb, barium Ba or strontium Sr is preferred.
  • particulate filter eliminates the particulates in exhaust gas.
  • a similar effect of eliminating particulates is achieved if other noble metals, alkaline metals, alkaline earth metals, rare earth elements and transition metals are used.
  • exhaust gas includes a great amount of excessive air. That is, if the ratio of air and fuel supplied to the intake passage and the combustion chamber is referred to as the air-fuel ratio of exhaust gas, the air-fuel ratio is lean. Because NO is generated in the combustion chamber, exhaust gas includes NO. Fuel includes sulfur S, which reacts with the oxygen in the combustion chamber and turns into SO 2 . Therefore, exhaust gas includes SO 2 . Accordingly, the exhaust gas including excessive oxygen, NO and SO 2 flows into the exhaust gas upstream side of the filter 70.
  • Figs. 23A and 23B are general enlarged views of the contact surfaces of the exhaust gas in the particulate filter 70.
  • Figs. 23A and 23B show a particle 60 of platinum Pt and active oxygen release agent 61 including kalium K.
  • Exhaust gas includes a great amount of excessive oxygen as described above. Therefore, if exhaust gas contacts the surfaces in the particulate filter 70, oxygen elements O 2 adhere to the surface of platinum Pt in the form of O 2 - or O 2- as shown in Fig. 23A.
  • the NO in exhaust gas reacts with O 2 - or O 2- on the surface of platinum Pt and turns into NO 2 (2NO + O 2 ⁇ 2NO 2 ). A portion of the produced NO 2 is then absorbed into the active oxygen release agent 61 while being oxidized on platinum Pt. Coupled with kalium K, NO 2 is diffused into the active oxygen release agent 61 in the form of nitrate ion NO 3 - as shown in Fig. 23A, and produces kalium nitrate KNO 3 .
  • exhaust gas also includes SO 2 , which is also absorbed into the active oxygen release agent 61 by a mechanism similar to that of NO. That is, as described above, oxygen elements O 2 adhere to the surface of platinum Pt in the form of O 2 - or O 2- , and the SO 2 in exhaust gas reacts with O 2 - or O 2- on the surface of platinum Pt and turns into SO 3 . A portion of the produced SO 3 is absorbed into the active oxygen release agent 61 while being further oxidized on platinum Pt. Coupled with kalium K, SO 3 is diffused into the active oxygen release agent 61 in the form of sulfate ion SO 4 2- and produces kalium sulfate K 2 SO 4 . In this manner, kalium nitrate KNO 3 and kalium sulfate K 2 SO 4 are produced in the active oxygen release agent 61.
  • the kalium nitrate KNO 3 formed in the active oxygen release agent 61 is decomposed into kalium K, oxygen O and NO.
  • the oxygen O moves towards the contact surface between the particulate 62 and the active oxygen release agent 61, and NO is released from the active oxygen release agent 61 to the outside.
  • the NO released to the outside is oxidized on the downstream platinum Pt and again absorbed into the active oxygen release agent 61.
  • the kalium sulfate K 2 SO 4 formed in the active oxygen release agent 61 is also decomposed into kalium K, oxygen O and SO 2 .
  • the oxygen O moves towards the contact surface between the particulate 62 and the active oxygen release agent 61, and SO 2 is released from the active oxygen release agent 61 to the outside.
  • the SO 2 released to the outside is oxidized on the downstream platinum Pt and again absorbed into the active oxygen release agent 61.
  • kalium sulfate K 2 SO 4 has been stabilized and thus is more unlikely to release active oxygen than kalium sulfate KNO 3 .
  • the oxygen O moving towards the contact surface between the particulate 62 and the active oxygen release agent 61 is decomposed from compounds such as kalium nitrate KNO 3 and kalium sulfate K 2 SO 4 .
  • the oxygen O decomposed from a compound is high in energy level and demonstrates an extremely high degree of activity. Accordingly, the oxygen moving towards the contact surface between the particulate 62 and the active oxygen release agent 61 is active oxygen O. If the active oxygen O comes into contact with the particulate 62, the particulates 62 are oxidized within a short time, a few minutes to dozen of minutes, without generating luminous flames.
  • NOx are diffused in the active oxygen release agent 61 in the form of nitrate iron NO 3 - while repeatedly connecting to and separating from oxygen atoms. Active oxygen is generated also during this period. This active oxygen oxidizes the particulates 62 also. Further, the particulates 62 that have thus adhered onto the particulate filter 70 are oxidized by active oxygen O but are oxidized also by oxygen in exhaust gas.
  • Platinum Pt and the active oxygen release agent 61 are activated in proportion to the increase in temperature of the particulate filter 70.
  • the amount of the active oxygen O that can be released from the active oxygen release agent 61 per unit time increases in proportion to the increase in temperature of the particulate filter 70.
  • particulates are more likely to be removed by oxidization as the temperature of the particulates themselves increases. Accordingly, the amount of the particulates that can be eliminated through oxidization on the particulate filter 70 per unit time without generating luminous flames increases in proportion to the increase in temperature of the particulate filter 70.
  • Fig. 24 shows with a solid line the amount G of the particulates that can be eliminated through oxidization per unit time without generating luminous flames.
  • the axis of abscissa represents the temperature TF of the particulate filter 70.
  • Fig. 24 shows the amount of particulates G that can be removed by oxidization in the case where the unit time is one second, i.e., per one second, the unit time can be an arbitrary length of time such as one minute, ten minutes, etc. For instance, in the case where the unit time is ten minutes, the amount of particulates G that can be removed per unit time by oxidization represents the amount of particulates G that can be removed per ten minutes by oxidization.
  • the amount of particulates G that can be removed per unit time by oxidization on the particulate filter 70 without luminous flame is likewise increased as the temperature of the particulate filter 70 increases, as shown in Fig. 24
  • the amount of the particulates discharged from the combustion chamber per unit time is referred to as the amount M of discharged particulates. If the amount M of discharged particulates is smaller than the amount G of the particulates that can be eliminated through oxidization as in a zone I shown in Fig. 24 all the particulates discharged from the combustion chamber are eliminated through oxidization on the particulate filter 70 successively within a short time without generating luminous flames when they come into contact with the particulate filter 70.
  • Figs. 25A, 25B, and 25C show how a particulate is oxidized in such a case. That is, in the case where the amount of active oxygen is insufficient to oxidize all the particulates, if the particulate 62 adheres to the active oxygen release agent 61 as shown in Fig. 25A, only a portion of the particulate 62 is oxidized, and the portion of the particulate 62 that has not been oxidized sufficiently remains on the carrier layer.
  • the portion of the particulate that has not been oxidized gradually remains on the carrier layer one after another. As a result, as shown in Fig. 25B, the surface of the upstream side of the filter is covered with a remaining particulate portion 63.
  • the remaining particulate portion 63 is gradually transformed into a carbon material, which is unlikely to be oxidized. Thus the remaining particulate portion 63 tends to remain where it is. If the surface of the upstream side is covered with the remaining particulate portion 63, the NO- and SO 2 -oxidization effect of platinum Pt and the active oxygen release effect of the active oxygen release agent 61 are weakened. As a result, one particulate 64 after another is accumulated on the remaining particulate portion 63 as shown in Fig. 25C. That is, particulates are accumulated in a laminated manner. If particulates are thus accumulated in a laminated manner, the particulates are no longer oxidized by active oxygen O.
  • particulates Even if the particulates are likely to be oxidized, they are not oxidized by active oxygen because they are spaced apart from platinum Pt and the active oxygen release agent 61. Thus one particulate after another is accumulated on the particulate 64. Namely, if the amount M of discharged particulates remains greater than the amount G of the particulates that can be eliminated through oxidization, particulates are accumulated in a laminated manner on the particulate filter. Therefore, the accumulated particulates cannot be burnt through ignition unless exhaust gas or the particulate filter 70 is heated up.
  • particulates are oxidized on the particulate filter 70 within a relatively short period without generating luminous flames in the zone I shown in Fig. 24, and particulates are accumulated in a laminated manner on the particulate filter in the zone II shown in Fig. 24.
  • the particulates being accumulated in a laminated manner on the particulate filter can be prevented by matching the relation between the amount M of discharged particulates and the amount G of the particulates that can be eliminated through oxidization corresponding to the relation indicated in the zone I shown in Fig. 24.
  • the pressure loss of exhaust gas flow in the particulate filter 70 scarcely changes and is maintained at a substantially constant minimum pressure loss value.
  • the decrease in engine output can be maintained at its minimum value.
  • the particulates may be accumulated on the particulate filter.
  • the electric control unit 30 controls the valve body 71 a to operate according to the first flowchart in Fig. 26 to prevent the accumulation of the particulates on the filter. The process of this flowchart is repeated for a certain time period.
  • the control units determines whether the valve is switched or not. The valve switching timing is determined by a predetermined time or to be determined by a certain mileage of the vehicle. If determined No, the procedure terminates and if determined Yes, proceeds to step 102 to rotate the valve body 71a from the current interrupting position to the other interrupting position.
  • Figs. 27A and 27B show an enlarged cross section of the partition wall 54 of the filter.
  • the exhaust gas upstream side front surface of the partition wall 54 and the flow opposing surface of the exhaust gas in the fine holes collect the particulate by collision as a collecting surface and removes the collected particulates by active oxygen discharged from the active oxygen release agent by oxidization.
  • the vehicle may be operated under the zone I in Fig. 24 and the particulates remain on the grid as shown in Fig. 27A due to insufficient oxidization. This small amount accumulation may not influence on the driving of the vehicle but if the amount of accumulation becomes larger, the engine output may be reduced to a great amount.
  • the remaining particulates on one side of the collecting surface of the partition wall 54 are oxidized to be removed by not only the active oxygen released from the collecting surface but also the remaining active oxygen used by the oxidization on the other side of the collecting surface by reversing of the exhaust gas flow.
  • the switching timing of the valve body 71a is not necessarily made periodical. It may be switched every time the engine is decelerated. The determining of deceleration can be made by the driver's intention to decelerate vehicle such as release of the accelerator or depression of the brake pedal or a fuel cut operation.
  • the difference (M-G) is regarded as the accumulation amount of the particulates wherein, M is the discharged particulates amount assumed by the current engine operation condition and G is the possible oxidization amount considering the particulates temperature assumed by the current engine operation condition.
  • the oxygen toxicities of the platinum Pt can be resolved every time the air-fuel ratio is changed from lean to enrichment to accelerate the oxidization of the particulates on the filter 70 by the increase of the discharge amount of the active oxygen at the time of lean air-fuel ratio. Further, the resolving of the oxygen is combustion of the deoxidization substance and accordingly the temperature of the particulate filter 70 increases with heat generation. The oxygen removable particulates are increased on the filter and the oxygen of remaining and accumulated particulates on the filter are easily removable.
  • the other collecting surface of the partition wall on which no particulates remain is easy to release the active oxygen compared to the one side surface and accordingly the remaining particulates on the one side surface can be surely oxidized due to the large amount of released active oxygen. It is also acceptable to enrich the air-fuel ratio of the exhaust gas independently of the switching operation of the valve body 71a not to generate the remaining or the accumulation of the particulates on the filter.
  • the low temperature combustion can be conducted. It is also acceptable to simply enrich the combustion air-fuel ratio.
  • the fuel can be injected to the cylinder by the engine fuel injection valve during the exhaust or expansion stage (post-injection) or during the intake procedure. It is not necessarily to provide an interval between the main fuel injection and such post-injection or VIGOM injection. It is also possible to supply fuel in the engine exhaust system.
  • the particulate filter of the embodiment absorbs the NOx in the exhaust gas but the filter structure is a wall through type in which the exhaust gas passes through the fine holes of the collecting wall. Compared to the type that the exhaust gas passes along the partition wall carrying the catalyst, the distance between the collecting walls has to be large enough to pass through the exhaust gas of the same amount.
  • the possibility of contacting with the active oxygen release agent carried on the collecting wall surface of the filter is smaller compared to the monolith type catalyst device.
  • the exhaust gas passes through the fine holes of the collecting wall, the exhaust gas contacts with the active oxygen release agent carried on the collecting surface wall, but mainly contacts only with the active oxygen release agent carried on the collecting surface.
  • the catalyst carrying area of collecting wall surface is not so large. Accordingly, even if the active oxygen release agent absorbing the NOx is carried on the particulate filter, the NOx in the exhaust gas is not sufficiently purified.
  • the catalyst device 73 carrying the noble metal and the substance which is capable of using as the active oxygen release agent for catalyst of NOx deoxidization catalyst according to the embodiment is provided in the intermediate flow portion 71c of the central conduit member 71 to the position always at the downstream side of the particulate filter independently of the reversing operation of the upstream side and downstream side of the filter.
  • the NOx, which has not been absorbed at the filter, can be absorbed to sufficiently decrease the discharge to the atmosphere.
  • NOx catalyst carried by the catalyst device 73 is not limited to the NOx deoxidization catalyst but the other catalyst such as NOx selective deoxidization catalyst may be used for purifying NOx.
  • the exhaust gas with a rich air-fuel ratio exhaust gas including the deoxidization substance flows into the particulates or the exhaust gas having a relatively large amount of HC and CO by conducting the low temperature combustion, flows into the particulate filter, not always all the deoxidization substances are oxidized by the noble metal of the filter or used for the NOx deoxidization discharged from the active oxygen release agent and therefore, the deoxidization substances passing through the filter have to be purified.
  • the device is always positioned at the downstream side of the filter 70 and close to the filter. Accordingly, by the oxidization removal of the particulates by the active oxygen at the filter and the combustion of the deoxidization substances by the noble metal, the particulate filter 70 is heated to transmit the heat from the filter to the catalyst device 73 to heat the catalyst device 73 thereby to sufficiently activate the catalyst.
  • the noble metal of the filter is not activated and the oxidization removal of the particulates and the combustion of the deoxidization substances are not sufficient.
  • the filter cannot be heated early. Accordingly, it takes a long time to transmit the heat from the filter to the catalyst to heat up. During this time period, the harmful substances such as HC, CO, and NOx are discharged to the atmosphere.
  • the catalyst device is warmed up at the early stage as shown in the flowchart in Fig. 28.
  • step 201 it is determined whether the engine condition is immediately after the starting or not. If determined to be No, the process terminates here. If Yes, at step 202 the valve body 71a is positioned at the intermediate position. The exhaust gas directly flows into the catalyst device 73 bypassing the filter 70 not to be cooled and it is possible to warm up the catalyst device. At step 203, the exhaust gas itself is heated to increase the temperature. This temperature control is made by supplying fuel in the cylinder during the exhaust stage by post-injection to keep the combustion during the exhaust stage to heat the exhaust gas temperature.
  • the exhaust gas passing through the catalyst device 73 passes around the particulate filter 70 at the downstream portion 71 d of the central conduit member 71 and the exhaust gas does not pass through the filter but the temperature of the filter is increased.
  • the temperature sensor 76 as the temperature of the catalyst device 73 detects the temperature of the exhaust gas at direct downstream side of the catalyst device 73 and it is determined whether the detected temperature T reaches the temperature T1 of the activation of the catalyst carried by the catalyst device 73. If determined Yes, the warm up of the catalyst device 73 is assumed to have been completed and at step 205, the temperature increase control of the exhaust gas is terminated.
  • the valve body 71a is set to be either of the two interrupting positions.
  • the temperature of the catalyst device may also be possible to detect the exhaust gas temperature flowing into the catalyst device (the exhaust gas temperature at direct upstream side of the catalyst device) and the temperature of the catalyst device can be assumed based on this temperature. It is also possible to assume the temperature of the exhaust gas flowing into the catalyst device in accordance with the engine operation condition as the catalyst device.
  • the exhaust gas flows into the particulate filter only after the completion of the warm up of the catalyst device 73 to start the collection of the particulates. Before that, the particulates are exposed to the atmosphere.
  • the completion of the warm up of the catalyst device takes not so long and this can be neglected.
  • the temperature of the filter is increased to an extent and the amount of particulates for oxidization is improved.
  • the effective oxidization of the particulates is possible from the beginning of collection thereof.
  • the temperature of the filter is low and oxidization of the particulates cannot be achieved efficiently at this stage. Under such condition, if the collection of the particulates begins, the particulates are accumulated on the filter to generate a clogging. It is preferable not to flow the exhaust gas into the filter immediately after the engine starting to prevent the clogging of the filter.
  • the catalyst device 73 functions sufficiently at the timing of flowing the exhaust gas into the filter to purify a part of the deoxidization substances passing through the filter.
  • the NOx absorbing deoxidization catalyst cannot purify the NOx effectively when the catalyst temperature is too high or too low.
  • the NOx absorbing deoxidization catalyst has an optimal temperature range of about 300 °C to 500 °C for effectively purifying NOx.
  • the catalyst device carries the NOx absorbing deoxidization catalyst, it is necessary to control the temperature thereof to the range described above. However, if simply the exhaust gas passing through the particulate filter 70 is introduced into the catalyst device, such control cannot be performed to decrease the purification function of the catalyst device.
  • the temperature of the catalyst device is controlled according to the flowchart shown in Fig. 29.
  • the temperature sensor 76 detects the exhaust gas temperature T directly downstream of the catalyst device 73 as the catalyst temperature and it is determined whether the catalyst temperature T is equal to or more than the lower temperature limit T1 (300 °C). If determined to be No, at step 302 the valve body 71a is positioned at the intermediate position and the exhaust gas bypasses the filter and directly flows into the catalyst device. At the step 303, the temperature increase control for the catalyst device is conducted. This temperature control means to include relatively large amount of the deoxidization substances in the exhaust gas by any of the methods described above. The deoxidization substances are combusted by the noble metal catalyst carried by the catalyst device and this combustion heat increases the temperature of the catalyst device.
  • the temperature of the exhaust gas flowing into the catalyst device can be warmed up. Either way of temperature control, it is possible to effectively increase the temperature of the catalyst device since the exhaust gas is directly introduced into the catalyst device preventing the consumption of the deoxidization substances at the filter or cooling of the exhaust gas.
  • the determination at step 301 is Yes, and the program proceeds to step 304 to determine whether the temperature is lower than or equal to the upper limit temperature T2 (500 °C) or not. If determined No, at step 305, the valve body 71a is positioned at the intermediate position and the exhaust gas bypasses the filter to directly flow into the catalyst device. At step 306, the temperature deoxidization control for the catalyst device is conducted.
  • the low temperature control means that the low combustion conducted at the lean air-fuel ratio or theoretical air-fuel ratio. The combustion temperature is decreased by the low temperature combustion to lower the exhaust gas temperature to decrease the temperature of the catalyst device.
  • the exhaust gas includes more deoxidization substances to increase the temperature.
  • Lowering the exhaust gas by a fuel cut can also achieve the temperature decrease control.
  • the fuel cut is difficult when the engine is under acceleration, no problems may occur under the driving conditions other than the acceleration even if an instant fuel cut is conducted. It is possible to decrease the temperature of the catalyst device by repetition of the instant fuel cutting operation. Waiting the engine deceleration, the valve body 71a is switched to the intermediate position and at the same time cutting fuel.
  • the exhaust gas is directly introduced into the catalyst device and it can effectively decrease the temperature of the catalyst device without heating the exhaust gas by removing the particulates at the filter by oxidization.
  • the determinations at both steps 301 and 304 are Yes, and when the temperature control is conducted at step 307 this control is stopped and when the valve body 71a is positioned at the intermediate position at step 308, the exhaust gas is allowed to be passing through the filter by switching the valve body 71a to either of the interrupting positions.
  • the interrupting position is set to be the other interrupting position different from the one before the valve body 71a being at the intermediate position. This will reverse the upstream side and downstream side of the filter to prevent the logging of the filter as explained above.
  • the catalyst carried by the catalyst device 73 as the NOx absorbing deoxidization catalyst includes the upper and lower temperature limits that function effectively, it is necessary to control the temperature increase and decrease controls, but when the oxidization catalyst is carried on the catalyst device, the temperature that functions effectively is only the lower limit and it is not necessary to control the temperature decrease at steps 304 and 306.
  • the catalyst device is located at the downstream side of the filter and the relatively large amount of the bulk of particulates separated from the filter flows into the catalyst device together with the exhaust gas and remains at the inlet of the catalyst device or within the catalyst device to increase the exhaust resistance of the catalyst device.
  • the upstream side and downstream side of the filter is reversed and when the large amount of particulates are accumulated on the filter due to some reasons, the bulk of the particulates are easy to be separated from the filter.
  • the separation of the particulates from the filter means that the particulates are removed from the filter to prevent the clogging of the filter.
  • the temperature of the filter may increase to become very high which might damage the filter by melting. It is therefore effective to avoid such risk.
  • the fourth flowchart prevents the remaining separated particulates from the catalyst.
  • step 401 it is determined whether the brake pedal is depressed by using a brake switch or the like. If determined No, the procedure terminates and if determined Yes, at step 402 the exhaust throttle valve 75 is opened to increase the exhaust gas resistance to generate the exhaust brake force.
  • step 403 the valve body 71a is positioned to the intermediate position. Normally when the brake pedal is depressed, the engine decelerates and combustion by the fuel cut operation is not conducted. Thus the particulates are not included in the exhaust gas and accordingly, the particulates are not discharged to the atmosphere even if the valve body 71a is positioned at the intermediate position and the exhaust gas bypasses the filter.
  • step 404 it is determined whether the depressed brake pedal is released or not. This determination is repeated until the determination becomes Yes.
  • the exhaust throttle valve 405 is opened at step 405 assuming that the vehicle deceleration is no more necessary.
  • the exhaust gas the pressure of which has become very high at the upstream of the exhaust throttle valve, passes through the valve at one time.
  • the flow rate of this exhaust gas is very high and is introduced into the catalyst device directly via the valve body 71a being at the intermediate position. Then the remaining bulk of the particulates in the catalyst device is destructed and discharged to the downstream side of the catalyst device. Thus it is possible to remove the bulk of particulates from the catalyst device.
  • the valve body 71a is switched to one of the interrupting positions from the intermediate position.
  • the interrupting position of the valve body 71a is preferably to the other interrupting position different from the one before the valve body 71a being at the intermediate position.
  • the valve body 71a immediately before the exhaust throttle valve 75 being open, the valve body 71a has been positioned at the intermediate position to allow the high speed exhaust gas to flow directly into the catalyst device by bypassing the filter at the valve 75 opening.
  • the high-speed exhaust gas flows into the catalyst device surely and prevents the bulk of particulates from separating from the filter.
  • the high-speed exhaust gas for positively separating the particulates from the filter.
  • the exhaust throttle valve is positioned at the upstream side of the catalyst device, it is not limited to that position and may be positioned at the downstream side of the catalyst device. According to this position of the exhaust throttle valve, the exhaust gas flowing slowly in the catalyst device can flows with a high speed in the catalyst device by the closing of the exhaust throttle valve to remove the bulk of the particulates from the catalyst device as mentioned above.
  • the NOx absorbing deoxidization catalyst when carried by the catalyst device 73, it is necessary to decrease the catalyst device temperature below the upper temperature limit value but when the catalyst device 73 is located downstream of the filter 70, practically the temperature of the catalyst device rarely increases beyond the upper limit value and in order to keep the temperature of the catalyst device to be more than the lower limit value, it is necessary to increase the temperature as much as possible.
  • the oxidization catalyst is carried on the catalyst device 73, in this case the upper temperature limit does not exist it is necessary to increase the temperature as much as possible.
  • Fig. 31 shows the fifth flowchart in which at step 501, it is determined whether the engine is decelerated or not. Detecting the depression of the acceleration pedal or the release of the pedal makes this determination. If determined No, the procedure terminates and if determined Yes, at step 502, the valve body 71a is positioned to the intermediate position and the exhaust gas flows directly into the catalyst device by-passing the filter. At step 503, the temperature increase control is made.
  • This temperature increase control is as is the same with the third flowchart the deoxidization substances in the exhaust gas are included as much as possible.
  • the deoxidization substances are combusted by the noble metal, which is carried by the catalyst device, and it is possible to increase the temperature by the combustion heat generated thereby.
  • the temperature increase control is made by post fuel injection to increase the exhaust gas temperature at the exhaust stage. Either way of temperature control, it is possible to effectively increase the temperature of the catalyst device since the exhaust gas is directly introduced into the catalyst device preventing the consumption of the deoxidization substances at the filter or cooling of the exhaust gas.
  • step 504 it is determined whether the deceleration of the engine is terminated or not. This determination is repeated until the determination becomes Yes to continue the temperature increase operation.
  • the temperature increase control is stopped and at step 506, the interrupting position of the valve body 71a is preferably to the other interrupting position different from the one before the valve body 71a being at the intermediate position.
  • the calcium In the presence of SO 3 , in the calcium Ca in the exhaust gas, the calcium produces calcium sulfate CaSO 4 .
  • Calcium sulfate CaSO 4 is difficult to be oxidized and remains on the filter as an ash. Accordingly in order to prevent the clogging of filter by the calcium sulfate CaSO 4 an alkaline metal or an alkaline earth metal that is higher in ionization tendency than calcium Ca, such as kalium K, is used as the active oxygen release agent 61, the SO 3 diffused into the active oxygen release agent 61 is coupled with kalium K and forms kalium sulfate K 2 SO 4 , and calcium Ca passes through the partitions of the particulate filter 70 without being coupled with SO 3 and flows through the partition wall of the filter.
  • an alkaline metal or an alkaline earth metal that is higher in ionization tendency than calcium Ca such as kalium K
  • the particulate filter 70 is prevented from being clogged.
  • an alkaline metal or an alkaline earth metal that is higher in ionization tendency than calcium Ca namely, kalium K, lithium Li, cesium Cs, rubidium Rb, barium Ba or strontium Sr be used as the active oxygen release agent 61.
  • the invention is also applicable to a case where only a noble metal such as platinum Pt is carried on the carrier layers formed on the front and back surfaces of the particulate filter 70.
  • a solid line indicating the amount G of the particulates that can be eliminated through oxidization is slightly offset to the right of the solid line shown in Fig. 24.
  • active oxygen is released from the NO 2 or SO 3 retained on the surface of platinum Pt.
  • a cerium Ce is used as an active oxygen release agent.
  • the cerium Ce absorbs oxygen when the oxygen concentration in the exhaust gas is high (Ce 2 O 2 ⁇ 2CeO 2 ) and if the concentration of the oxygen decreases, the active oxygen is discharged (2Ce 2 O 2 ⁇ Ce 2 o 3 ).
  • the air-fuel ratio of the exhaust gas is enriched periodically or non-periodically.
  • cerium Ce Fe or Sn may be used.
  • the NOx absorbing deoxidization catalyst may be used for purifying NOx in the exhaust gas.
  • the air-fuel ratio of the exhaust gas is necessary to be temporarily enriched for discharging the NOx or SOx.
  • the particulate filter itself carries the active oxygen release agent to oxidize the particulates by the active oxygen released from the active oxygen release agent, but it is not limited to such structure.
  • the particulate oxidization component such as active oxygen and CO 2 which functions equal to the active oxygen may be discharged from the filter or the substance carried thereon or may flow into the particulate filter from outside.
  • the first collecting surface and second collecting surface of the collecting wall are alternately used wherein the one collecting surface which becomes the downstream side has no accumulation of further newly flown particulates and the accumulated particulates are gradually oxidized to be removed by the particulate oxidization component flown from the other side collecting surface to sufficiently remove the accumulated particulates taking a time to a certain extent.
  • the other collecting surface collects the particulates and oxidizes by the oxidization component of the particulates. This can achieve the same effects as above.
  • the diesel engine according to the embodiment conducts the lower temperature combustion and higher temperature combustion by switching them, but the invention is not limited to this method and diesel engine conducting only the normal combustion is acceptable or the gasoline engine discharging the particulates may be applicable to this invention.
  • the catalyst device 73 as described is of a normal monolith type but the catalyst device 731 of type having a cross section as shown in Fig. 32 may be used.
  • the catalyst device 731 shown in Fig. 32 includes a plurality of partition walls 731a extending in axial direction and formed by porous materials such as cordierite as same with the particulate filter 70 in the outer frame 731e.
  • the inside of the catalyst device 731 is divided into a plurality of spaces by each partition wall 731a.
  • One partition wall 731a surrounding one of the two adjacent axial spaces 731b forms a tapered portion 731c tapered toward outside at exhaust gas upstream side and the other partition wall 731a surrounding the other of the two adjacent spaces 731b forms another tapered portion 731c tapered toward outside at exhaust gas downstream side.
  • Each tapered portion 731c is in quadratic conic shape when the axial space 731b is rectangular in cross section and the conical shape of the tapered portion 731c is variable depending on the shape of the axial space 731c in cross section.
  • the opening area of the axial space 731b surrounded by the tapered portion 731c at the upstream side of the exhaust gas is far larger than the cross section area (at central portion) of the axial space 731c.
  • the tapered portion 731c can be formed by deforming one end of the partition wall 731a.
  • the tapered portions 731c at both upstream and downstream sides of the exhaust gas do not close the respective corresponding axial spaces 731b and each has a passage 731d which has a smaller area in cross section than the cross section area of the corresponding axial space 731.
  • the exhaust gas flowing into the catalyst device 731 flows into about half of the axial spaces 731b having tapered portions 731c at the upstream side of the exhaust gas via a passage 731d having a smaller cross section area as shown with the dashed arrow line.
  • the exhaust gas flowing into the catalyst device 731 flows into the other half of the axial spaces 731b without tapered portions 731c at the upstream side of the exhaust gas via a large opening and in total the exhaust gas flow resistance is not so different in value from the monolith type catalyst device.
  • the part of the exhaust gas flowing into the corresponding axial space 731b via the large opening flows out via the passage 731d of the tapered portion 731c as shown with the dashed arrow line since the axial space 731b includes the tapered portion 731c at the downstream side of the exhaust gas.
  • main flow of the exhaust gas passes through the partition wall 731a surrounding the axial space 731b and flows out from the adjacent axial space 731b.
  • the exhaust gas easily passes through the catalyst device 731.
  • Each partition wall 731a carries the NOx absorbing deoxidization catalyst, NOx selective deoxidization catalyst or the oxidization catalyst as similar to the catalyst device 73.
  • the catalyst device 731 the catalyst device 731 can purify the harmful substances such as NOx or deoxidization substances in the exhaust gas passing through the particulate filter 70 before they are discharged to the atmosphere.
  • the catalyst device 731 since the catalyst device 731 is structured to have the partition walls 731a, through each of which the exhaust gas passes, the particulates can be collected by the partition walls as is the same with the particulate filter 70.
  • the exhaust gas containing the particulates bypasses the filter 70.
  • the particulates are collected by the catalyst device 731 and are not discharged to the atmosphere.
  • the catalyst device 731 receives only the particulates in the exhaust gas that bypass the filter 70 and the particulates that cannot be collected and the possibility that the particulates are collected by the catalyst device 731 beyond the oxidization removable particulates of the catalyst device 731 is small based on the method similar to the particulate filter 70.
  • the exhaust gas flows into the corresponding space 731b of the tapered portion 731c at the upstream side of the exhaust gas even if the exhaust gas cannot pass through each partition wall 731a due to the accumulation of the particulates since the catalyst device 731 is provided with the passage 731d at the tapered portion 731c and then flows out from the corresponding axial space 731b. Further the exhaust gas flows into the large opening adjacent to each tapered portion 731c at the exhaust gas upstream side and flows out from the passage 731d of the tapered portion 731c at the exhaust gas downstream side.
  • the exhaust gas at this time contacts with the catalyst carried on the surface of the partition walls 731a upon passing through the catalyst device 731 to purify the harmful substances such as HC, CO and NOx in the exhaust gas corresponding the carried catalyst.
  • Fig. 33 is a cross sectional view showing a first modification of the catalyst device 731 explained in Fig. 32. Only the difference from the catalyst device 731 will be explained hereinafter.
  • a plug 732c is provided instead of the tapered portion 732b at the exhaust gas upstream side and the corresponding axial space 732b is closed by the plug 732c at the upstream side of the exhaust gas.
  • the tapered portion at the downstream side of the exhaust gas is omitted.
  • Outer frame 732e is a partition wall made from the porous material.
  • the exhaust gas is surrounded by the axial space 732b closed by the plug 732c and flows into the axial space, which is not provided with the plug 732c.
  • a part of the exhaust gas flows out from the axial space 732b but other part of the exhaust gas flows out from another axial space 732b adjacent to this axial space 732b passing through the partition wall 732a.
  • the particulates in the exhaust gas passing through the partition wall 732a are collected by the wall 732a.
  • the collected particulates by the partition wall 732a is as same with the catalyst device in Fig. 32 is oxidized to be removed by the active oxygen discharged from the catalyst carried by the partition wall 732a. Even if a large amount of the particulates are accumulated on the partition wall 732a, the exhaust gas flows into the axial space 732b, which is not provided with the plug 732c and flows out from the axial space 732b to prevent the malfunction of vehicle operation caused by the unusual large flow resistance of the catalyst 732a.
  • the exhaust gas at this time contacts with the catalyst carried on the surface of the partition walls 732a upon passing through the catalyst device 732 to purify the harmful substances such as HC, CO and NOx in the exhaust gas corresponding the carried catalyst.
  • Fig. 34 is a cross sectional view showing a second modification of the catalyst device 731 explained in Fig. 32. Only the difference from the catalyst device 731 will be explained hereinafter.
  • an axial space 733b which is not provided with a plug 733c at the exhaust gas upstream side, the catalyst coating layer 733d (for example alumina) for carrying the catalyst on the partition wall 733a is thickened only at the downstream side of the exhaust gas.
  • the cross section area of the axial space 733b without plug 733c is throttled to restrict the flowing of the exhaust gas from the axial space 733b.
  • the flow of the exhaust gas indicated with the dashed arrow line cannot collect the particulates in the exhaust gas but by reducing the flow amount directly passing through the axial space 733b, most of the particulates in the exhaust gas flowing into the catalyst device 733 can be collected by the partition walls 733a.
  • the exhaust gas flows into the axial space 733b that is not provided with the plug 733c and flows out from the axial space 733b to prevent the malfunction of vehicle operation caused by the unusual large flow resistance of the catalyst 733a.
  • the exhaust gas at this time contacts with the catalyst carried on the surface of the partition walls 733a upon passing through the catalyst device 733 to purify the harmful substances such as HC, CO and NOx in the exhaust gas corresponding the carried catalyst.
  • Fig. 35 is a cross sectional view showing a third modification of the catalyst device 731 explained in Fig. 32. Only the difference from the catalyst device 731 will be explained hereinafter.
  • a thick catalyst layer 734d is provided as similar to the second modification.
  • the same effects can be achieved by this modification as the catalyst device 731 in Fig. 32. Since it is easier to provide the thick catalyst layer 734d rather than providing the passage 734f by forming a tapered portion 734c by the partition wall 734a, the catalyst device 734 is easy to be manufactured compared to the catalyst device 731 of Fig. 32.
  • the catalyst device 734 of this modification is further easier to be manufactured by substituting the tapered portion 734c and the passage 734f at the upstream side of the exhaust gas for as same with the downstream side the thick catalyst layer.
  • Fig. 36 is a cross sectional view showing a fourth modification of the catalyst device 731 explained in Fig. 32. Only the difference from the catalyst device 731 will be explained hereinafter.
  • a plug 735c is provided at the downstream side of the exhaust gas and instead of providing the thick catalyst layer at the downstream side of the exhaust gas, a thick catalyst layer 735d is provided at the upstream side of the exhaust gas.
  • the partition wall 735a surrounding the axial space 735b is chamfered to make the opening of the axial space large at the upstream side of the exhaust gas. Accordingly, the exhaust gas is easy to be flown into the axial space 735b.
  • the exhaust gas flowing into the catalyst device 735b flows into the about half of the axial spaces 735b each having a large opening at the upstream side of the exhaust gas and as shown with the dashed line, the exhaust gas flows into the other half of the axial spaces 735b throttled by the thick catalyst layer 735d at the upstream side of the exhaust gas.
  • the axial spaces 735b having the large opening are closed by the plug 735c at the downstream side of the exhaust gas and the exhaust gas flown into the axial spaces 735b flow out of the adjacent spaces 735b by passing through the partition walls 735a surrounding the axial spaces 735b as shown with the solid arrow line.
  • the particulates collected by the partition walls 735a as the catalyst device in Fig. 32, are removed by the oxidization by the active oxygen released from the catalyst carried by the partition walls 735a.
  • the exhaust gas flows into the axial space 735b which is not provided with the plug 735c and flows out from the axial space 735b to prevent the malfunction of vehicle operation caused by the unusual large flow resistance of the catalyst device 735.
  • the exhaust gas at this time contacts with the catalyst carried on the surface of the partition walls 735a upon passing through the catalyst device 735 to purify the harmful substances such as HC, CO and NOx in the exhaust gas corresponding the carried catalyst.
  • Fig. 37 is a plane view showing another embodiment of the exhaust gas purifier and Fig. 38 shows a side view of the purifier of Fig. 37.
  • the difference with the purifiers shown in Figs. 18 and 19 is the position of the catalyst device 73'.
  • the catalyst device 73' is positioned around the outer case 70a of the particulate filter 70 within the downstream portion 71d of the central conduit member 71.
  • the shape of the cross section of the catalyst device 73' is the shape which removes a rectangular cross sectional shape of the central outer case 70a from the circular cross sectional shape when the downstream portion 71d is circular in cross section.
  • the catalyst device 73' is located more closer to the particulate filter 70 compared to the one in the exhaust gas purifier described in the previous embodiment.
  • the discharged heat via the outer case 70a of the filter 70 can be used mainly for heating the catalyst device 73' by the position of the catalyst device 73'.
  • the discharged heat amount from the particulate filter 70 can be reduced, which means that the particulates for oxidization removal of the filter 70 can be increased by keeping the high temperature of the filter itself.
  • the effective heat transfer from the catalyst device 73' to the filter can be achieved in reverse to increase the particulates for oxidization removal by heating the particulate filter 70. It is true that the catalyst device 73 of the previous embodiment can raise the temperature of the filter 70 by the heat transfer when the temperature is sufficiently increased.
  • the catalyst device 73' can carry the catalyst which is same as the catalyst carried by the catalyst device 73 and the monolith type carriers or the carriers shown in Figs. 32 to 36 can be also applicable.

Claims (22)

  1. Eine Abgasreinigungsvorrichtung weist einen Partikelfilter (70) auf, der in einem Motorabgassystem zum Auffangen von Partikeln angeordnet ist, eine Umkehreinrichtung (71a), die eine Seite stromauf eines Abgasstroms und eine stromabwärtige Seite des Abgasstroms des Partikelfilters (70) umkehrt, wobei die aufgefangenen Partikel an dem Partikelfilter (70) oxidiert werden, wobei der Partikelfilter (70) eine Auffangwand zum Auffangen der Partikel aufweist, die Auffangwand eine erste Auffangoberfläche und eine zweite Auffangoberfläche aufweist, und wobei die erste und die zweite Auffangoberfläche abwechselnd zum Auffangen von Partikeln durch Umkehren der Seite stromauf des Abgasstroms und der stromabwärtigen Seite des Abgasstroms des Partikelfilters (70) durch die Umkehreinrichtung (71a) verwendet werden, wobei die Abgasreinigungsvorrichtung dadurch gekennzeichnet ist, daß sie folgende Merkmale aufweist:
    eine Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73'), die benachbart zu dem Partikelfilter (70) an einer Position angeordnet ist, die sich stets an der stromabwärtigen Seite des Abgasstroms des Partikelfilters (70) befindet.
  2. Abgasreinigungsvorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß ein Aktivsauerstofffreisetzungsmittel durch die Auffangwand getragen wird, und ein aktiver Sauerstoff, der von dem Aktivsauerstofffreisetzungsmittel freigesetzt wird, die Partikel oxidiert.
  3. Abgasreinigungsvorrichtung nach Anspruch 2, dadurch gekennzeichnet, daß das Aktivsauerstofffreisetzungsmittel den Sauerstoff auffängt und einbehält, wenn um das Aktivsauerstofffreisetzungsmittel herum ein Sauerstoffüberschuß vorliegt, wobei das Aktivsauerstofffreisetzungsmittel den einbehaltenen Sauerstoff als aktiven Sauerstoff freisetzt, wenn eine Sauerstoffkonzentration um das Aktivsauerstofffreisetzungsmittel herum gesenkt wird.
  4. Abgasreinigungsvorrichtung nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') einen Oxidationskatalysator trägt.
  5. Abgasreinigungsvorrichtung nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') einen NOx-Katalysator trägt.
  6. Abgasreinigungsvorrichtung nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die Umkehreinrichtung (71a) einen Ventilkörper aufweist und die Seite stromauf des und die stromabwärtige Seite des Partikelfilters (70) durch Schalten des Ventilkörpers von einer ersten Position auf eine zweite Position umkehrt, wobei das Abgas in die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') direkt einströmt, ohne durch den Partikelfilter (70) zu gelangen, wenn der Ventilkörper auf eine Zwischenposition zwischen der ersten und der zweiten Position geschaltet ist.
  7. Abgasreinigungsvorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß der Ventilkörper (71a) unmittelbar nach Start des Motors an der Zwischenposition positioniert ist.
  8. Abgasreinigungsvorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß die Abgasreinigungsvorrichtung ferner eine Temperaturerfassungseinrichtung (76) aufweist, die eine Temperatur der Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') erfaßt oder annimmt, wobei der Abgaszustand verändert wird, so daß er innerhalb eines vorbestimmten Temperaturbereichs liegt, wenn die durch die Temperaturerfassungseinrichtung (76) erfaßte oder angenommene Temperatur der Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') von dem vorbestimmten Temperaturbereich abweicht, indem der Ventilkörper in die Zwischenposition positioniert wird.
  9. Abgasreinigungsvorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß ein Abgasdrosselventil (75) in dem Motorabgassystem vorgesehen ist, und der Ventilkörper (71a) an die Zwischenposition positionierbar ist, bevor das Abgasdrosselventil öffnet.
  10. Abgasreinigungsvorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß, wenn der Motor abgebremst wird, der Ventilkörper (71a) an der Zwischenposition positioniert ist und zumindest die Abgastemperatur erhöht wird oder die Menge der Desoxidationssubstanzen im Abgas erhöht wird.
  11. Abgasreinigungsvorrichtung nach Anspruch 7, dadurch gekennzeichnet, daß die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') benachbart stromab des Ventilkörpers angeordnet ist.
  12. Abgasreinigungsvorrichtung nach einem der Ansprüche 1 bis 11, dadurch gekennzeichnet, daß die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') näher am Verbrennungsmotor angeordnet ist als der Partikelfilter (70), wobei die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') mit dem Partikelfilter (70) verbunden ist, so daß das Abgas, das aus dem Partikelfilter (70) herausströmt, in die Katalysatorvorrichtung einströmt.
  13. Abgasreinigungsvorrichtung nach einem der Ansprüche 1 bis 12, dadurch gekennzeichnet, daß die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') folgende Merkmale aufweist:
    eine Trennwand (73a, 731a, 732a, 733a, 734a, 735a), die aus einem porösen Material gebildet ist und das Innere der Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') in eine Mehrzahl von axialen Räumen unterteilt;
    einen Strömungsmengen-Steuerabschnitt (52, 53, 731c, 732c, 733c, 733d, 734c, 734d, 735c, 735d), der an zumindest entweder einem Ende stromauf des oder einem stromabwärtigen Ende des axialen Raums angeordnet ist und eine Strömungsmenge des Abgases steuert.
  14. Abgasreinigungsvorrichtung nach Anspruch 13, dadurch gekennzeichnet, daß der Strömungsmengen-Steuerabschnitt (52, 53, 731c, 732c, 733c, 733d, 734c, 734d, 735c, 735d) an dem Ende stromauf der Trennwand angeordnet ist, die einen von zwei benachbarten axialen Räumen umgibt.
  15. Abgasreinigungsvorrichtung nach Anspruch 13, dadurch gekennzeichnet, daß der Strömungsmengen-Steuerabschnitt (52, 53, 731c, 732c, 733d, 734c, 734d, 735c, 735d) an dem stromabwärtigen Ende der Trennwand angeordnet ist, die einen von zwei benachbarten axialen Räumen umgibt.
  16. Abgasreinigungsvorrichtung nach Anspruch 13, dadurch gekennzeichnet, daß der Strömungsmengen-Steuerabschnitt ein Stopfen (52, 53, 732c, 733c, 735c) ist, der entweder an der Seite stromauf oder der stromabwärtigen Seite von jeweils einem axialen Raum angeordnet ist und ein Strömen des Abgases verhindert.
  17. Abgasreinigungsvorrichtung nach Anspruch 13, dadurch gekennzeichnet, daß der Strömungsmengen-Steuerabschnitt ein verjüngter Abschnitt (731c, 734c) ist, der einen Öffnungsbereich des axialen Raums vergrößert oder reduziert.
  18. Abgasreinigungsvorrichtung nach Anspruch 17, dadurch gekennzeichnet, daß der verjüngte Abschnitt (731c, 734c) mit einem Durchlaß (731d, 734f) versehen ist, der über einen Querschnitt verfügt, der kleiner als ein Querschnitt des axialen Raums ist.
  19. Abgasreinigungsvorrichtung nach Anspruch 17, bei der der verjüngte Abschnitt (731c, 734c) durch Verformen der Trennwand (731a, 734a) ausgebildet ist.
  20. Abgasreinigungsvorrichtung nach Anspruch 13, dadurch gekennzeichnet, daß der Strömungsmengen-Steuerabschnitt eine Katalysatorbeschichtungsschicht (733d, 734d, 735d) ist, die einen Katalysator auf der Trennwand trägt.
  21. Abgasreinigungsvorrichtung nach einem der Anspruch 1 bis 20, dadurch gekennzeichnet, daß sowohl der Partikelfilter (70) als auch die Katalysatorvorrichtung (73, 731, 732, 733, 734, 735, 73') in einem Gehäuse (72) angeordnet sind.
  22. Abgasreinigungsvorrichtung nach einem der Ansprüche 1 bis 21, dadurch gekennzeichnet, daß die Katalysatorvorrichtung (73') um den Partikelfilter (70) herum positioniert ist.
EP02007169A 2001-03-29 2002-03-28 Abgasreiniger für eine Brennkraftmaschine Expired - Lifetime EP1245801B1 (de)

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Families Citing this family (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6964256B2 (en) * 2002-03-28 2005-11-15 Mazda Motor Corporation Combustion control apparatus for an engine
JP3738752B2 (ja) * 2002-05-21 2006-01-25 トヨタ自動車株式会社 内燃機関用マフラ
JP3985053B2 (ja) * 2002-07-15 2007-10-03 マツダ株式会社 エンジンの排気微粒子処理装置
CN100371563C (zh) * 2002-10-16 2008-02-27 三菱扶桑卡客车公司 用于内燃机的废气净化系统
JP4369141B2 (ja) 2003-02-18 2009-11-18 日本碍子株式会社 ハニカムフィルタ及び排ガス浄化システム
SE527527C2 (sv) * 2003-04-02 2006-04-04 Volvo Lastvagnar Ab Motordrivet fordon med avgasrening
DE10325183B4 (de) * 2003-06-04 2013-01-31 Robert Bosch Gmbh Verfahren und Vorrichtung zur Durchführung eines Verfahrens zur Ermittlung des Beladungszustands eines in einem Abgasbereich einer Brennkraftmaschine angeordneten Bauteils
JP4285096B2 (ja) * 2003-06-16 2009-06-24 株式会社デンソー 内燃機関の排ガス浄化装置
GB0314243D0 (en) * 2003-06-18 2003-07-23 Johnson Matthey Plc Engine exhaust gas treatment
US6883311B2 (en) * 2003-07-02 2005-04-26 Detroit Diesel Corporation Compact dual leg NOx absorber catalyst device and system and method of using the same
FR2862103B1 (fr) * 2003-11-07 2006-02-17 Peugeot Citroen Automobiles Sa Systeme d'aide a la regeneration de moyens de depollution integres dans une ligne d'echapement d'un moteur diesel de vehicule automobile
US20060053774A1 (en) * 2004-09-15 2006-03-16 Kabasin Daniel F Exhaust treatment system and methods using the same
US7263824B2 (en) * 2004-12-03 2007-09-04 Cummins, Inc. Exhaust gas aftertreatment device for an internal combustion engine
US20060251548A1 (en) 2005-05-06 2006-11-09 Willey Ray L Exhaust aftertreatment device
CA2508159C (en) * 2005-05-24 2009-05-05 Ecocing Corporation Improved reversing flow catalytic converter for internal combustion engines
DE102005045294B4 (de) * 2005-09-22 2021-11-18 Daimler Ag Verfahren zum Betreiben einer Brennkraftmaschine
FR2895017B1 (fr) * 2005-12-20 2008-01-25 Renault Sas Procede et systeme de regeneration du filtre a particules d'un moteur thermique
EP1801372B1 (de) * 2005-12-22 2011-03-30 ARK-Holding AG Partikelfilteranordnung und Verfahren zum Filtern von Abgasen
JP4259546B2 (ja) * 2006-07-13 2009-04-30 トヨタ自動車株式会社 火花点火式内燃機関
US20080120968A1 (en) * 2006-11-29 2008-05-29 Douglas Munroe Beall Partial wall-flow filter and diesel exhaust system and method
US20080141662A1 (en) * 2006-12-14 2008-06-19 Markus Schuster Fluid injecting and mixing systems for exhaust after-treatment devices
JP5103910B2 (ja) * 2007-01-23 2012-12-19 マツダ株式会社 ディーゼルエンジンの排気浄化装置
US7931715B2 (en) * 2007-02-12 2011-04-26 Gm Global Technology Operations, Inc. DPF heater attachment mechanisms
US7862635B2 (en) * 2007-02-12 2011-01-04 Gm Global Technology Operations, Inc. Shielded regeneration heating element for a particulate filter
KR101020819B1 (ko) * 2008-11-28 2011-03-09 기아자동차주식회사 흡장형 ＮＯｘ 촉매의 후분사용 가변 분사장치와 그 분사방법
US8388712B2 (en) * 2009-02-12 2013-03-05 Ford Global Technologies, Llc Particulate matter retaining and purging system
US20110041482A1 (en) * 2009-08-20 2011-02-24 Gm Global Technology Operations, Inc. Method and apparatus for exhaust aftertreatment of an internal combustion engine
US8521399B2 (en) * 2009-12-08 2013-08-27 Ford Global Technologies, Llc System and method for reducing particulate matter produced by an engine
JP5440385B2 (ja) * 2010-05-25 2014-03-12 いすゞ自動車株式会社 排ガス浄化システム
DE102013211661A1 (de) * 2012-08-03 2014-02-06 Ford Global Technologies, Llc Verbrennungsmotor mit Direkteinspritzung und reduzierter Feinstaubemission
AT520706B1 (de) * 2017-12-01 2020-10-15 Avl List Gmbh Abgasnachbehandlungssystem
JP2021504627A (ja) * 2017-12-01 2021-02-15 アー・ファウ・エル・リスト・ゲー・エム・ベー・ハーＡｖｌ Ｌｉｓｔ Ｇｍｂｈ 排ガス後処理システム

Family Cites Families (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2946651A (en) * 1956-08-09 1960-07-26 Oxy Catalyst Inc Catalytic treatment of gas streams
US4535588A (en) * 1979-06-12 1985-08-20 Nippon Soken, Inc. Carbon particulates cleaning device for diesel engine
JPS5713211A (en) * 1980-06-30 1982-01-23 Nippon Soken Inc Minute particle purifier for internal combustion engine
JPS5765812A (en) * 1980-10-09 1982-04-21 Nippon Soken Inc Purifier for removing particle from exhaust gas of in ternal combustion engine
JPS5874862A (ja) * 1981-10-29 1983-05-06 Nippon Soken Inc デイ−ゼルエンジンのｅｇｒ装置
DE3232729A1 (de) * 1982-09-03 1984-03-08 Degussa Ag, 6000 Frankfurt Verfahren zur herabsetzung der zuendtemperatur von aus dem abgas von dieselmotoren herausgefiltertem dieselruss
US4562695A (en) * 1983-12-27 1986-01-07 Ford Motor Company Particulate trap system for engine exhaust using electrically powered regeneration
US4923487A (en) * 1988-10-17 1990-05-08 The Duriron Company, Inc. Cross flow diesel particulate trap
DE4004424A1 (de) 1989-02-15 1990-08-16 Steyr Daimler Puch Ag Vorrichtung zum reinigen der abgase von dieselmotoren
JPH0598932A (ja) 1991-10-04 1993-04-20 Nissan Motor Co Ltd 内燃機関の排気浄化装置
JP2722987B2 (ja) 1992-09-28 1998-03-09 トヨタ自動車株式会社 内燃機関の排気浄化装置
JPH07106290A (ja) 1993-09-30 1995-04-21 Matsushita Electric Ind Co Ltd 電子部品用異物除去装置
JP3303495B2 (ja) 1993-12-28 2002-07-22 株式会社デンソー 内燃機関の排気浄化装置
JPH08229330A (ja) * 1995-02-28 1996-09-10 Sumitomo Electric Ind Ltd ディーゼルエンジン用パティキュレートトラップ
JPH0913946A (ja) * 1995-06-28 1997-01-14 Mitsubishi Heavy Ind Ltd 黒煙除去装置を備えた排ガス浄化装置
JP3387290B2 (ja) 1995-10-02 2003-03-17 トヨタ自動車株式会社 排ガス浄化用フィルター
US5768888A (en) * 1996-11-08 1998-06-23 Matros Technologies, Inc. Emission control system
JP3645704B2 (ja) * 1997-03-04 2005-05-11 トヨタ自動車株式会社 内燃機関の排気浄化装置
EP0984142B1 (de) 1997-04-24 2004-06-30 Toyota Jidosha Kabushiki Kaisha Abgasüberwachungssystem für verbrennungsmotoren
US6167696B1 (en) * 1999-06-04 2001-01-02 Ford Motor Company Exhaust gas purification system for low emission vehicle
US6293096B1 (en) * 1999-06-23 2001-09-25 Southwest Research Institute Multiple stage aftertreatment system
JP3558015B2 (ja) 1999-07-12 2004-08-25 トヨタ自動車株式会社 内燃機関の排気ガス浄化方法
US6314722B1 (en) * 1999-10-06 2001-11-13 Matros Technologies, Inc. Method and apparatus for emission control
WO2002008580A1 (fr) 2000-07-24 2002-01-31 Toyota Jidosha Kabushiki Kaisha Dispositif de commande de l'emission des gaz d'echappement d'un moteur a combustion interne

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EP1245801A2 (de) 2002-10-02
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JP3624892B2 (ja) 2005-03-02
EP1245801A3 (de) 2003-06-18
DE60201367D1 (de) 2004-11-04
US6655133B2 (en) 2003-12-02
JP2002357115A (ja) 2002-12-13

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